Inherently larger, Tahoma has to be set in a slightly smaller size compared to Georgia but as both have very similar inner structures on closer examination, a harmonious marriage is actually possible. Depending on the context, the sans or the serif could be utilised for the main copy, while a variant of the other can provide emphasis. And with careful handling of the measure, leading and so forth, (other typographic details might need a little scripting), the result can be pretty harmonious.
Prior to reading The Elements of Typographic Style, most of my typographic choices fell into the realm of arbitral selection. And even now, my knowledge still remains very naive.
Even so, with all the care and detail one can put into screen based typography, there are still limitations which have to be overcome with either programmatic workarounds or bluntly: hacks. Small-caps, for example, is a lost cause for web. Unless main copy trickled with blemishes of computed small-caps, or some form of text replacement technique, acceptable small-caps are hard to come by. Even the highly anticipated @font-face has its limitations in cross browser implementation. Even the text indentation applied to the paragraphs seen here require certain selectors which are not implemented across all browsers.
A possible experiment is to utilise Javascript to automate the complex layout of multi-columned text, driven by a metadata ladened source.Javascript would probably be a likely and suitable solution to some of the limitations presented in contemporary web typography, filling in the gaps which browser makers are unable or unwilling to bridge. As such, an opportunity arise in this realm where visual and programmatic design overlap. Exciting times await.
Ideally, text on the web should both be written and presented in a considered manner; even though conventions seem to point otherwise, but with enough hope and optimism, practitioners like Jason Santa Maria who places effort in both the act of writing and layout, would be able to inspire others into following suit.